Auxin responsiveness in DR5::GUS transgenic lines selected by vectors with hptII controlled by tCUP1 promoter.

Both a3-DR5 (A–D) and c3-DR5 (E–H) transgenic lines using the tCUP1 promoter for hptII gene expression were selected for the auxin responsive test. Representative images are shown for two independent lines each showing the DR5 promoter strongly induced in primary root tips (B, F) and lateral roots (D, H) after 1 µM NAA treatment for 24 h. In the mock treatment, specific but different DR5::GUS expression was observed between a3-DR5 and c3-DR5 lines in primary root tips (A, E) as well as in lateral roots (C, G). Bars: 100 µm.